COMPARISON OF THE HARTREE-FOCK, MOLLER-PLESSET, AND HARTREE-FOCK-SLATER METHOD WITH RESPECT TO ELECTROSTATIC PROPERTIES OF SMALL MOLECULES - EFFECTS OF ELECTRON CORRELATION
Gjm. Velders et D. Feil, COMPARISON OF THE HARTREE-FOCK, MOLLER-PLESSET, AND HARTREE-FOCK-SLATER METHOD WITH RESPECT TO ELECTROSTATIC PROPERTIES OF SMALL MOLECULES - EFFECTS OF ELECTRON CORRELATION, Theoretica Chimica Acta, 86(5), 1993, pp. 391-416
The results of various quantum chemical calculations, the Hartree-Fock
(HF) method, the Moller-Plesset perturbation theory (MP2), and the Ha
rtree-Fock-Slater (HFS) method are compared. Atomic charges, dipole mo
ments, topological properties of the electron density distribution and
polarizabilities, and first hyperpolarizabilities are calculated. Ato
mic charges obtained with the HFS method are found to be very close to
those calculated with the MP2 method, from which we conlcude that the
HFS method describes to some extent electron correlation effects. Per
forming an MP2 calculation after an HF calculation improves the molecu
lar dipole moments considerably, yielding values close to the experime
ntal ones. HFS calculations are computationally less demanding than MP
2 and yield comparable results for the electron density distributions,
dipole moments and polarizabilities.